甲烷一维层流预混火焰的详细和单步反应机理模拟  

Numerical simulations of one-dimensional laminar premixed CH_4/air flames using the detailed and one-step reaction mechanisms

作　　者：李卓毅[1] 张会强[1] 

机构地区：[1]清华大学航天航空学院,北京100084

出　　处：《清华大学学报（自然科学版）》2005年第11期1510-1512,1517,共4页Journal of Tsinghua University(Science and Technology)

基　　金：国家自然科学基金资助项目(10002009)

摘　　要：为了解单步反应机理的不足及其不同速率表达式之间的差异,分别采用详细和单步化学反应机理数值模拟了甲烷一维层流预混火焰。详细机理预报的火焰速度在整个可燃范围都与实验结果吻合,而单步机理只在贫燃条件下才能给出定量相符的结果,在富燃条件下定性和定量预报结果均不合理。同时,单步机理预报的温度和浓度分布也存在较大偏差,特别是在富燃区。进一步研究表明,用有些常见单步反应速率表达式获得的预报值在整个可燃范围都是不合理的。这些结果对选取反应模型和获得可信预报结果有参考意义。The shortcomings of the one-step reaction mechanism and the differences among different chemical reaction rate formulae were exhibited by simulating a one-dimensional laminar premixed flame using detailed and one-step reaction mechanisms. The flame speeds predicted by the detailed mechanism agree well with experimental results over the whole burning range, while those predicted by the one-step mechanism agree with experimental results only for fuel-lean conditions with quantitative and qualitative results being unreasonable the fuel-rich conditions. The results also show errors in the predicted temperature and concentration distributions when using the one-step mechanism, especially for the fuel-rich condition. In addition, predictions with some frequently used reaction rate formulae using the one-step mechanism are shown to be in correct over the whole burning range. The results can facilitate better reaction model selection and better predictions.

关 键 词：详细反应 单步反应 火焰速度 反应速率 

分 类 号：TK16[动力工程及工程热物理—热能工程]